Magnetic recording media using metal particles or having metal thin layers provided by vacuum deposition, sputtering or metal plating have been studied for high density recording. Some of these magnetic recording media are now practically used for audio tapes, etc. as disclosed in, for example, U.S. Pat. Nos. 3,047,423, 3,525,638, 3,117,896 and 2,900,282. However, these magnetic recording media do not necessarily have satisfactory stability to rust, oxidation, corrosion, changes in quality and the like which can be detected visually or in magnetic recording properties. In particular, these magnetic recording media have not yet been practically used as video tapes.